1. Field of the Invention
This invention relates to slide gates for controlling fluid flow and, more particularly, to an improved slide gate seal.
2. Description of the Prior Art
Slide gates are employed to control fluid flow through a passageway or channel. A slide gate has a frame assembly which defines an opening through which fluid flows, a slide comprising a slide plate selectively mounted to the frame assembly and adapted for vertical movement relative thereto so as to selectively open and close the opening, sealing members for providing a watertight seal between the slide plate and frame assembly, and operating means for vertically moving the slide between open and closed positions for regulating fluid flow through the opening. Generally, the frame assembly is mounted to the walls surrounding or defining the passageway or channel through which the fluid flows in such a manner that substantially all of the fluid flows through the opening in the frame assembly. In this way, fluid flow through the opening of the slide gate is determined by the position of the slide within the frame assembly. Typical slide gates and their sealing members are shown in U.S. Pat. Nos. 3,760,593; 4,028,896; 4,226,533; 4,848,962, and 5,141,361.
The degree of success attained by prior slide gates has been determined in part by the limitations of the seals which are used to provide a watertight connection between the slide and the frame assembly. The problems and disadvantages of prior seal designs are described in my U.S. Pat. No. 4,848,962 (hereafter the '962 Patent). To the extent that it is necessary to do so, the description of the prior art and the features and details of construction disclosed by the '962 Patent are incorporated herein by reference thereto.
The '962 Patent discloses certain improvements in slide gate seats which overcome limitations of prior commonly used seals. A significant advantage of the side seals disclosed in the '962 Patent is that they are adjustable to vary the amount of force exerted by them on the slide. However, the range of such adjustment is limited.